Foam?

Ok, so not sure if this has anything to do with chemistry or not. So when I went to do a water change tonight, I shut the pump off and a layer of bubbles/foam developed in the back chamber of my Biocube. It only appeared in the middle chamber and the one with the return pump. I have carbon and a heater in the first chamber, but nothing developed in there. I haven't noticed anything like it before and it only turned up after I shut the pump off to do the water change. Any ideas on what would cause this?

 

Where about is your protein skimmer located?

 

At the moment I don't have a skimmer. My livestock is pretty slim and I haven't gotten around to getting one. Plus, I've mixed reviews on the small ones.

 

The bubbles or foam could either be excess protein foaming at the surface, or nitrogen/gas bubbles being released from within live rock/sand, or gas bubbles from algae photosynthesizing.

 

I would recommend getting a protein skimmer even if it's a not as efficient small one, IME oxygenation from a skimmer in priceless in a tropical marine tank even if it doesn't skim as much out as a large skimmer, at least it would remove some of the organic nutrients.

 

Hydrophobic organic substances attached to bubbles. Once the water movement was stopped, the bubbles all went to the surface and were no longer circulated. This is exactly how a protein skimmer works.

And yes, this is chemistry at it's finest. What is Skimming? by Randy Holmes-Farley - Reefkeeping.com

 

the one i have on my biocube isnt awsome but it does pull out enough to make it worth $30 i paid for it